Syntheses of bismuth titanate templates obtained by the molten salt method

Abstract Bismuth titanate templates (Bi 4 Ti 3 O 12 ) were synthesized by the molten salt method in Na 2 SO 4 and K 2 SO 4 fluxes, using an amorphous Bi 4 Ti 3 O 12 precursor and a mechanically mixed Bi 2 O 3 +TiO 2 mixture as the starting materials. The templates were characterized by means of X-Ray Diffraction, FT-IR, FT-Raman, FEG-SEM and TEM. The templates are free of secondary phases and present orthorhombic structure with orientation in the c -plane. FT-IR suggests no traces of sulfate groups revealing that the molten salt synthesis was beneficial for elimination of inorganic species and for the arrangement of individual nanocrystals into ordered lattices. FEG-SEM analyses of BIT templates revealed that most of the grains were homogeneous with a length of 3.1 µm and a width of 0.3 µm and had plate-like morphology. TEM investigations show that the c -axis of the perovskite units is parallel to the thickness direction of the grains and no liquid-phase was formed during BIT phase formation.